Workpiece stopping devices are tools, collectively referred to as “stops”, and have been used in a variety of industries for many decades in order to readily repeat, on any number of workpieces, a prescribed length-related operation, such as cutting or drilling. More specifically, in a typical operation, one end of a workpiece is abutted or pressed against a workpiece stopping device in order that an operation being performed at the other end can be repeated with consistency and accuracy any number of times to accommodate a given quantity demand.
Workpiece stopping devices are commonly found in a variety of work shops where same-length cutting, drilling, machining, stamping, hammering, etching, engraving, bending, welding, grinding, scoring, riveting, marking, flaring, notching, printing, scanning, etc., operations occur. It is important to appreciate that these operations, with rare exception, occur in an indoor shop environment. As a result, three conditions pertain to these workpiece stopping devices:                1) the workpiece stopping device equipment is stationary or semi-stationary, that is, it might be moveable if outfitted with wheels, but generally resides in one location since, by requirement, may be very long and cumbersome to move about;        2) the workpiece stopping device equipment is configured as a track system which allows for quick and easy length adjustments along the full length of the track and can be as long as needed to accommodate a given requirement. (Such a piece of equipment can be found at www.flip-stop.com.)        3) the workpiece stopping device equipment is not designed to get wet or otherwise be subject to varied weather-related considerations (e.g., temperature, humidity, UV light, wind, etc.).        
In the construction industry in particular however, work is generally not performed in a work shop. Most construction work is performed in the field where the particular structure is being built and where most equipment is transported to on trucks driven by the workers. As a consequence, a workpiece stopping device that works in a shop does not, for all intents and purposes, work in the field. Portability is a key and mandatory component of all field related equipment. Portable, generally speaking, means: small/compact, light weight, easy to lift, easy to carry, easy to move, easy to store, easy to assemble/disassemble, etc. Workpiece stopping devices found in a shop environment simply do not meet these requisite field demands.
There are many facets to a construction project and a common, albeit occasional, activity that is required when building virtually any structure of interest, such as a commercial building, an apartment building, a house, or a deck, is to cut any number of workpieces to a single prescribed length—which are then installed by the workers; typical application include: studs that make up a wall, treads required in a staircase assembly, and balusters as an aesthetic and safety component to a railing system. Accordingly, in order to avoid measuring each workpiece individually, creating potential variability and consuming an inordinate amount of time, repetitive same-length cutting operations require setup of a workpiece stopping device.
When a project begins, workers arrive at the job site with their equipment on their vehicles, typically setup one shared work station—because of the substantial space requirements of the construction materials and tool requirements of all the workers—and proceed to distribute the various tasks among themselves. A typical work station includes a compound miter saw as the primary tool for all workers to use in order to cut the variety of stock-sized workpieces (e.g. 2×2, 2×6, 5/4×6, etc.) to the desired lengths and angular end-cut criteria needed. Of course, sharing the work station can lead to conflicts and inefficiencies, such as when a repetitive same-length cutting operation demands that the work station be dedicated, for a limited or extended period of time, to cutting many workpieces to a single prescribed length. To efficiently accomplish this repetitive cutting task the work station is configured so that the specific length to be cut is preset between the primary tool, i.e., the miter saw, and a workpiece stopping device. That is, the workpiece stopping device is located an exact distance, or length, away from the miter saw blade so that each piece pressed or abutted against to the workpiece stopping device is cut to the prescribed length each time. And it is important to appreciate that accuracy and consistency from one workpiece to the next is essential when making repetitive same-length cuts as each piece becomes part of a larger construction assembly and workpiece variability would create disorder within the construction.
It is also helpful, essential, to better understand the work environment. In the field of construction four conditions very commonly exist:                1) workers spend many days, weeks, or months on a given project, then move to another project taking their tools and equipment with them on their work trucks; a circumstance which also requires that workers be able to store their tools securely either in their trucks or on-site during off hours;        2) given the nature of the work, a construction project is physically demanding on tools and equipment and the job site is often outdoors (until a roof is built if the job calls for one) with exposure to a wide variety of weather and sun conditions;        3) construction projects are typically built by two or more workers using a shared work station comprising a compound miter saw as the primary tool;        4) structures are built plumb and square, and constructed with detailed accuracy as a primary goal.Accordingly, in terms of using a workpiece stopping device in the field of construction, the attributes of the device should consider: a) portability, b) durability, c) interruptibility, and d) accuracy. Taking each consideration in turn:        a) portability considers that virtually all tools and equipment are moved on work trucks with limited space and weight capacities; accordingly, it is preferable that a workpiece stopping device be relatively small/compact, light weight, easy to lift, easy to carry, easy to move, easy to store, easy to assemble/disassemble, etc.;        b) durability considers that construction tools need to withstand the rigors of outdoor use on a construction site; accordingly, a workpiece stopping device would be made of materials that are preferably strong and able to withstand the effects of sun (particularly UV) and weather;        c) interruptibility allows for use of a work station by more than one worker even after the workpiece stopping device has been located, arranged, and adjusted to meet specific length and abutment-end criteria; accordingly, it is preferable that a workpiece stopping device have the capability to be arranged in a specific obstructing configuration by a first worker, easily reconfigured into a non-obstructing position for the needs of a second worker, and be easily re-set back to the original configuration so that the first worker can quickly resume work;        d) accuracy is a desideratum in construction as it allows the various components to be assembled with greatest efficiency; accordingly it is preferable that a workpiece stopping device be true, precise, and substantial, while accommodating setup, adjustment, and transition requirements quickly and easily.        
An additional important concept with regard to the background art is to understand a tool's relative level of indispensability. That is, it's usefulness versus it's frequency of use, or the consideration of how well a tool does it's job relative to how often the tool is needed. Fundamentally, the objective of any tool (within or outside the field of construction) is to meet two goals:    1) make the work go faster;    2) do the work more accurately.These combined attributes influence the tool's usefulness. Usefulness then, combined with frequency of use, determines a tool's level of indispensability. Every tool achieves or fails to meet these criteria to one degree or another, from one user to another. By in large, the vast majority of construction tools are used infrequently. None-the-less many are considered indispensable. Most field tools do not fall into the high frequency use category such as a measuring tape, a hammer, or a circular saw, tools that are used many times a day on a typical project. Most tools fall into the infrequent use category such as a router, a reciprocating saw, or a laser level, tools that are generally used only occasionally, even rarely, but when needed, produce results that are exceptionally quick and exceptionally accurate, and accordingly achieve a high level of indispensability, i.e., must-own tools.
Referring now to FIG. 1, work station 20 is shown comprising miter saw 21 as the primary tool. Miter saw 21 rests on a conventional work surface 26 comprised of top planks supported by saw horses. It is preferable that work surface 26 be level, although not mandatory. Miter saw 21 includes a blade 22 and a cutting platform 24. Blade 22 contains cutting teeth which further defines cutting plane 23 on the side of blade 22. The relevant cutting plane 23 is on the side of blade 22 which is nearest temporary stop 30 (described below). Additionally, one or more rollers or other support structures 27 may be placed on work surface 26 and arranged at a height equal to cutting platform 24 of miter saw 21 to define resting plane 25 across the length of work surface 26. During a cutting operation a workpiece 10 (e.g., a 2×4) is positioned on resting plane 25 (i.e., on cutting platform 24 and extending outwardly left and right therefrom) and cut to a prescribed length L by activation of blade 22 of miter saw 21 wherein the blade is vertically lowered into workpiece 10 to make the cut. To accurately repeat the cut at length L a temporary stop 30 is secured to work surface 26 at the prescribed distance, or length L, away from cutting plane 23 of miter saw 21. Length L is measured from cutting plane 23 to a stop surface 31 of temporary stop 30. Upon establishing length L, temporary stop 30 is secured to work surface 26 with clamps, screws, or the like. This configuration now allows for any number of workpieces 10 to be cut to length L without the need to measure each workpiece 10. It should also be appreciated that the pieces arranged to produce temporary stop 30 must be stacked to a height above resting plane 25 such that temporary stop 30 can consistently block, obstruct, or otherwise stop a workpiece abutted against stop surface 31. Additionally, in this typical arrangement of such a work station, temporary workpiece stopping devices are generally constructed of scrap materials that are usually available during project construction.
A problem with respect to the characteristics of work station 20 is that after temporary stop 30 is secured in place other workers sharing the work station 20 are generally unable to use the miter saw 21 because the temporary stop 30 creates an obstruction whenever a workpiece 10 needs to be cut longer than the stop position, length L. As a result, other workers on the job have limited options in terms of maintaining productivity. Available options include:    1) waiting until the repetitive same-length cutting operation is complete;    2) dedicating the space and setting up a separate work station to do independent cutting;    3) making the cut(s) with a less precise and less versatile hand-held circular saw;    4) disassembling temporary stop 30 and reassembling it whenever an interrupting cut must be made.As can be appreciated, the four options are each fraught with unproductive and undesirable consequences.
Another problem with respect to the characteristics of work station 20 and temporary stop 30 is that there is no provision to support the abutment-end of workpiece 10 (i.e., the end of workpiece 10 away from miter saw 21 and abutting stop surface 31). As described above, resting plane 25 extends outwardly from cutting platform 24 of miter saw 21 and is coplanar with the top of support structures 27. If the material being cut, with its inherent structural limitations, extends too far beyond cutting platform 24 or too far beyond a support structure 27 before contacting stop surface 31, an excess cantilever will result causing the workpiece to bend, deflect, or otherwise sag downward from resting plane 25. This condition will invariably lead to cuts that are either too long or too short relative to the desired length.
Another problem with respect to the characteristics of work station 20 is that temporary stop 30 is inherently awkward and time-consuming to setup and adjust. The top portion of temporary stop 30 must always be higher than resting plane 25. This usually requires that temporary stop 30 be made in two or more pieces and are therefore subject to independent movement. This can then affect the ability of temporary stop 30 to maintain a fixed position. Further, because the materials are generally made from scrap, set-up requirements always vary. Accordingly, pieces comprised of the correct length, width, and thickness for a particular set-up may not be available. For example, if the project is in the earliest stages of construction or if a site cleanup was recently performed the appropriate materials may not be available; requiring that stop pieces be cut from new material, thereby creating undesirable waste. All of these factors contribute to setup difficulties, diminished reliability, and reduced productivity when working with temporary stop 30.
Referring now to FIG. 2, work station 40 is shown comprising miter saw 41 as the primary tool. Miter saw 41 connects to a portable miter saw stand 46 comprising extension arms 47 and a support/stop member, shown generally at 50. Similar to the previously described arrangement, miter saw 41 includes a blade 42, a cutting plane 43, a cutting platform 44, and a resting plane 45 which is defined by cutting platform 44 and extending outwardly left and right therefrom. It is preferable that resting plane 45 be level, although not mandatory. Adjustable length extension arms 47 extend outwardly, within limits, from each end of saw stand 46. If a heavy workpiece is being cut it is possible to insert a vertical support under extension arm 47, such as adjustable support post 48, an inverted “T”, to carry the overload. Mounted near the end of extension arm 47 is support/stop member 50 comprised of a short vertical post 51 to which is connected a support surface 52 the top of which is coplanar with resting plane 45. Attached to support surface 52 is a stopping mechanism 53 which is configured to provide a stop surface 54 when making repetitive same-length cuts and which can rotate out of the way when not in use. (Such a piece of equipment can be found at www.dewalt.com, search DWX723.)
A problem with respect to the characteristics of work station 40 is that support/stop member 50 is unreliable. Vertical post 51 is attached to extension arm 47 by means of a hand-tightened solitary center thumb knob and bolt—this configuration is prone to rotation and wobble. Additionally, vertical post 51 is fabricated in a telescoping fashion using hand-tightened thumb knobs in a dual-slotted arrangement to accommodate the variety of cutting platform 44 heights that exist on the variety of miter saws available on the market at the time of this writing—the resulting assembly is problematic to set up and easily disrupted—i.e., unreliable.
Another problem with respect to the characteristics of work station 40 is that miter saw stands, given the requirements of portability, demand that the stands be made of relatively thin-walled, light-weight materials, e.g., aluminum. As a consequence, as extension arm 47 is extended or lengthened, it becomes less and less supportive, i.e. as cantilevers lengthen they become progressively less able to support a load, resulting in a structure that is decreasingly sturdy, more unstable, less able to produce consistent same-length cuts—i.e., also unreliable. While use of support post 48 under extension arm 47 can help with sag caused by heavier/longer workpieces, it does not prevent a back-and-forth swaying action that can occur as workpieces become heavier/longer—regardless of the attempt to counter such movement with the inverted “T” provision—i.e., further unreliable.
Another problem with respect to the characteristics of work station 40 is that use of support/stop member 50 is restricted to the two length extremes of extension arm 47. That is, if repetitive cuts are required to be longer or shorter than the available extremes of extension arm 47, the support/stop member 50 is unavailable, thus diminishing the versatility of work station 40.
Another problem with respect to the characteristics of work station 40 is that it is extremely difficult to produce fine length adjustments of stop surface 54 of support/stop member 50 relative to miter saw 41. The only way to make length adjustments is to slide extension arm 47 in-and-out of saw stand 46; an awkward adjustment method particularly as the unit get older and dirt and sawdust enter the extension arm guide channels. Also, there is no provision to angle the stop surface 54, relative to the longitudinal orientation of workpiece 10, when needed to accommodate a particular abutment-end angular condition.
Another problem with respect to the characteristics of work station 40 is that support/stop member 50 cannot be used independently. It cannot be used in other repetitive same-length operations such as when a workpiece stopping device is required for use with a floor model drill press or punch-press. That is, the support/stop member 50 is only workable as part of extension arm 47 and is generally not available otherwise.
Referring now to FIG. 3, work station 60 is shown comprising miter saw 61 as the primary tool. Miter saw 61 rests on a portable work stand 66. A channel track stopping assembly is comprised of one or more of each of the following: channel track 67, support structure 68, and slideable stop member, shown generally at 70. Similar to the previously described arrangements, miter saw 61 includes a blade 62, a cutting plane 63, a cutting platform 64, and a resting plane 65 which is defined by cutting platform 64 and extending outwardly left and right therefrom. In addition to work stand 66 needed to support miter saw 61, at least one section of channel track 67 (two sections of channel track 67 are shown) is attached to at least one side of cutting platform 64 of miter saw 61, the top of which is coplanar with resting plane 65. Aside from the end(s) attached to cutting platform 64, the end of each section of channel track 67 must be carried and stabilized by a support structure 68 (two support structures 68 are shown). Additionally, after the first channel track 67 is attached to cutting platform 64 of miter saw 61, each added section of channel track 67 must comprise a section connector (not shown) in order to attach an additional section to a previous section. Optimally, miter saw 61, work stand 66, channel tracks 67, and support structures 68 are configured to produce a substantially straight and level, contiguous system. Each channel track 67 comprises a slide channel (not shown) contiguous through all track sections, to accommodate the back-and-forth sliding capability of stop member 70. Stop member 70, comprised of stop arm 73 and stop surface 74, is arranged along channel track 67 for use in making repetitive same-length cuts; stop arm 73 and stop surface 74 can be rotated out of the way when not in use. (Such a piece of equipment can be found at www.sawhelper.com, search Ultrafence.)
A problem with respect to the characteristics of work station 60 is that setup of the track system is onerous. Channel tracks 67, by necessity, must be of a limited size to optimize portability, rigidity, and storage requirements (i.e., typically about 1.4 m or 54″ long). Setup is substantial and time-consuming as each joint and each section of channel track 67 must be carefully assembled, supported, leveled, and adjusted to a correct height, relative to resting plane 65. One, two, or three sections of channel track 67 may be needed on just one side of miter saw 61 to accomplish a given repetitive same-length cutting operation; but to make the system most useful, the components must be available and the setup process must be undertaken on both sides of miter saw 61—thereby doubling the equipment and effort required to make a complete, substantially straight, and level assembly.
Another problem with respect to the characteristics of work station 60 is that work stand 66 and support structures 68, when used away from a paved level surface, can be difficult to set up particularly if the supporting ground is irregular, uneven, sloping, soft, wet, spongy, or a combination of these conditions; or the condition of the supporting ground may be acceptable one day, but due to changeable weather conditions, could be unacceptable the next day. Generally, paved surfaces to set up equipment are atypical at construction sites and if a paved surface does exist it's usually too far away from the work at hand to be helpful, i.e., generally, the closer the equipment is to the work being performed, the more productive the crew will be.
Another problem with respect to the characteristics of work station 60 is the relative instability and lack of strength throughout the system. The requirements for portability demand that the channel track 67 sections be made of relatively thin-walled, light-weight materials, e.g., aluminum, which subsequently requires relatively frequent support, even in the absence of relatively weak/flexible section connections. The use of frequent support structures 68 helps manage the weight of the construction materials being cut but the entire assembly is relatively fragile and susceptible of being moved out of alignment or being knocked over on a job site. Further, as additional sections of channel track 67 are added, the portions of the track furthest away from the miter saw 61 become inherently less stable and more prone to accidental damage, even wind damage. Additionally, because of the relative fragility of the system, the work station ought to be set up and dismantled each work day; leaving the assembly unattended and exposed to potentially destructive elements (e.g., weather hazards or ill-intentioned visitors) is very risky.
Another problem with respect to the characteristics of work station 60 is the relatively large storage requirements of the several and varied components that can make up a workable system—as well as the consideration that the components are often stored in construction vehicles, which are sometimes remote from a work area. So not only must a considerable amount of space be dedicated to accommodate the size and quantity of the various components, the time consideration to assemble/disassemble and transport the several parts twice a day, from storage to work station and back, is very problematic. Further, it is essential to appreciate that during a typical construction project, repetitive same-length cutting operations, although performed regularly, are required only occasionally, not frequently, and as such make the considerable storage and time requirements of this system unfortunate.
Another problem with respect to the characteristics of work station 60 is that stop member 70 cannot be used independently. It cannot be used in other repetitive same-length operations such as when a workpiece stopping device is required for use with a floor model drill press or punch-press. That is, the stop member 70 is only workable as part of channel track 67 and is generally not available otherwise.
Accordingly, there is need for improvement with respect to stopping devices used at work stations; the portable workpiece stopping device described herein and shown in the various embodiments elucidates many such improvements.